Adhesive and method of its manufacture



Patented Feb. 15,1927.

= ,UNITEDMSTATVES,

LOUIS FACKLER,

P TENT oFFIca,

or 'menwoon; nnw mnsnir, nssrcnon no 'rrm srnm-nnvms' comrm, on NEW YORK, n. Y.,

A conrone rron or new Yonx."

emmsrvn m runner) or 11's mun-Acetone.

No Drawing.

in cold water, but is also substantially color less and will neither gelatinize nor decompose on standing over relatively long periods of time. p

By reason of the highly complicated character of the substances which impart color to dextrine and the lack of accurate knowledge of their composition, no indication of the possibility of bleachingdextrine has, so far as I am aware, been available. Furthermore, the fact that the manufacture of dextrine is usually carried out as a dry process has presented practical difficulties to bleaching which have heretofore not been sun,

mounted.

. I have discovered that certain oxygen carriers, under proper conditions, will yield oxygen, probably in a nascent state, to a solution containing a dextrine and that this action causes a bleaching or elimination *of the color-bearing constituents vof the dextrim. The chemistry of this action is highly involved and by no means settled and I therefore Will not attempt to describe the chemical action which is believed to take place.

I preferably employ a dextrine of tenacious consistency when mixed, which in its naturalstate is quite dark. -By my process, however, I am able to bleach dextrines of this type so that they will form when mixed a substantially colorless product and readily go into solution even when cold. -'I also pro-.

duce an intermediate product, comprising a dry dextrine and a dry alkaline perborate which may be sold in a dry state and mixed when desired by the ultimate consumer.

In practising my improved process, I may start-with a dextrine' prepared in any suit-. able manner, such as many of the processes well-known to the prior art and in'com- ,mercial practice; as for instance, the sub- Ipplication filed December 15; 1921. serial No. $28 ,458.

jecting of starch or starch-bearing material.

to the action of heat, or heat and acid, or

many examples of which are to. be found in known process of using heat and anacid is some other agent used for thepurpose .of'

breaking down the starch. cell structure,

used, [a brownish colored product is pro Q- duced, which is difiicultly solublev in cold water because of its-tendency' to ball up, forming slowly soluble agglomerations. This condition is sometimes remedied in practice by the addition of'borax to the dextrine,;but in all processes with which I am familiar, whether an agent to assist solubility is used or not, the solution obtained is relatively highly colored and is consequently unusable for many purposes in the art; as for instance, white paper sizing; the gluing of light-colored or colorless papers; etc.

Forthe production of certain products, as for instance, a heavy glue suitable for use in box-making machinery, I prefer to start with a dextrine which contains an, admix ture of borax as stated above; but it will be understood that myinvention is equally applicable to dextrines to which no borax has been added, or even dextrines which have a slightly acid content. As will be pointed out hereafter, my improved process may in a measure dispense with borax to obtain the solubility required in certain instances.

As an instance of a form of my procez's which I have found to be useful, 1 may add to a suitable dextrine, an alkaline perborate; such, for instance, as'a perborate of sodium to the extent of about one to two per cent of the dextrine by WBlQllt. I find that from one to tWo per cent is usually sufficient to produce the bleachin action required, but I do not Wish to limit myself to this quantity, as an excess of the perborate of sodium may produce other useful results; such, for instance, as leaving'in the product decomposition products which will replace the borax heretofore used inwhole or in part. A convenient method of practising my process consists inmixing the dextrine and perborate of sodium in a substantially dry conditionand thereafter adding a. sufficient amount of water to form a sizing or adhesive of the consistency required. The water added may be either progressively greater change of color. as-

time goes on. The resulting product is substantially colorless =and-"has all of the ada hesiveproperties of adextrine glueor sizing made according to'the processes of the prior'art.- Some of my experiments indicate that enhanced adhesive properties are secured, but aside from the change in color the action of the oxygen carrier produces in general no appreciable changein the physical characteristics of the product; The reaction may occur in acid, alkaline or neutral solutions, and either at room temperature or under the influence of heat. A slight amount of heat hastens the reaction somewhat, but I prefer to maintain the temperature within moderatelimits in order to prevent foaming during the reaction.

My invention may also be practised in connection With the wet process for the manufacture of dextrine, by adding the alkaline perborate to the solution in which the dextrine is formed or to the dextrine containing solution after the formation. of

the dextrine While I preferablv employ a perborate of an alkali element, such as perborate of sodium, potassium or ammonium, I may, if desired, employ a perb'orate of an alkaline earth element, suchas a perborate of calcium, magnesium, etc., and I therefore in the claims employ the words alkaline perborate to include either the perborate of an alkali element or the perborate of an alkaline earth element A main feature of my invention is the step in the process of forming a substantially colorless liquid adhesive, which comprises adding to dextrine, either in a Wet or dry state,

aconstituent such as a perborate, which comprises a chemically combined dextrine solution accelerator, such as borax, and a bleaching element such as oxygen.- When water, either acid, neutral or alkaline, is added to this mixture, it decomposes the perborate to give off oxygen therefrom Whcre tionland the rdecomposedf,r esidu pound, probably borax, ma

by the freed oxygen may bleach solution accelerator, which is a boron comsolution' of v thedirtrine. {1 e11 that boron compounds function as dextrine asolution;-accelerators :aainduv also seem to increase the adhesiveness of the final product.

used and any type of alkaline peroorate,

' such as mentioned above-," mayfbe'employed Since the processes described above "are" intend to be'confinedthereto."

1. The process offor'm'ing colorless liquid adhesive, fwhich comprises,-

adding to .-dry dextrine-a dry perborate'ot' soda and adding water thereto-to decoinpose the perborate, whereby the oxygen freed from said perborate may bleach the solution and the decomposed residuary boron compound may accelerate the solution of the dextrine.

2. The step in the process of forming a substantially colorless liquid adhesive, which comprises, adding to dextrine a perborate of sodium.

'3. A composition of matter for use in a sette-.1 knfi'wn Any-"suitable type's of dextrineswmay bew given merely by Way of example-,I'donot a substantially forming a substantially colorless liquid adhesive containing-dry dextrine and a dry perborate of sodiu m.

4. The process of forming a substantially colorless liquid'adhesive, which comprises, 7

adding to dry dextrine a dry alkalineperborate and adding Water thereto to decompose the perborate, whereby the oxygen freed from said perborate may bleach the solution and the decomposed residuary boron compound may accelerate the solution of the dextrine.

5. The step in the process of forming a substantially colorless liquid adhesive, which comprises, adding to dextrine-an alkaline perborate.

6. A composition of matter for use in forming a substantially colorless liquid adhesive containing dry dextrine and a dry alkaline perborate.

In testimony whereof, I have signed myname to this specification this 14th day of December, 1921.

LOUIS FACKLER. 

